1. Technical Field
Embodiments of the inventive concepts relate to an image sensor, and more particularly, to an image sensor for distributing an output peak current and an image processing system including the same.
2. Description of the Related Art
A complementary metal oxide semiconductor (CMOS) image sensor is an image pickup device manufactured using CMOS processes. The CMOS image sensor has lower manufacturing cost and smaller pixel size than a charge coupled device (CCD) image sensor having a high-voltage analog circuit and thus has an advantage of low power consumption. In addition, with the improvement of the performance of CMOS image sensors, CMOS image sensors are widely used for mobile electronic devices such as smart phones, tablet personal computers (PCs), and digital cameras.
In high-resolution CMOS image sensors, a data bus is a block that finally processes digital signals corresponding to analog pixel signals output from pixels. When digital signals, i.e., image data are processed at high speed; a conventional CMOS image sensor usually transmit digital signals corresponding to column lines to buffers using a sensor amplifier. When the digital signals corresponding to the column lines are output to the buffers at the same time, a transient peak current may occur. The transient peak current may lead to the drop of voltage, which may severely affect high-speed circuits, e.g., analog-to-digital converters, which convert analog pixel signals into digital signals.